In the OLED display device in the related art, a Vss signal is input to the cathode by an IC (i.e. a driving circuit), and a Vdd signal is input to the anode by the IC. A voltage difference between the Vdd signal and the Vss signal is a driving voltage ΔV which drives the light-emitting material to emit light.
Since the data line in the OLED display device has a certain impedance, the Vdd signal at a distal end of the IC has a certain voltage drop compared to the Vdd signal at a proximal end of the IC, resulting in a difference in the driving voltage ΔV between the distal end and the proximal end of the IC and thus occurrence of a problem in long run uniformity (LRU), i.e., the long-run display brightness of the OLED display device is ununiform. Moreover, as the screen size increases, the average brightness of the display increases and the LRU becomes worse, making it difficult to achieve high-quality display, and especially for monochrome grayscale images, it can be evidently seen that the display brightness at the proximal end of the IC is higher than that at the distal end of the IC.